Glucoimidazole and polyhydroxycyclohexenyl amine derivatives to treat gaucher disease

ABSTRACT

The present invention provides glucoimidazole (GIZ) and polyhydroxycyclohexenyl amine (PHCA) derivatives, methods of making them, and methods of use where the GIZ and PHCA derivatives have a short, flexible linker emanating from the corresponding position of the ring oxygen in a pyranose; and a lipophilic moiety connected to the linker and pharmaceutically acceptable salts thereof. More particularly, the present invention further provides a method for treating individuals having Gaucher disease by administering the novel GIZ or PHCA derivatives as “active-site specific chaperones” for the mutant glucocerebrosidase associated with the disease.

This application claims priority to provisional application 60/519,496 filed Nov. 12, 2003, herein incorporated by reference.

FIELD OF THE INVENTION

The present invention provides novel glucoimidazole (GIZ) and polyhydroxy-cyclohexenyl amine (PHCA) derivatives having a short, flexible linker emanating from the corresponding position of the ring oxygen in a pyranose; and a lipophilic moiety connected to the linker and pharmaceutically acceptable salts thereof. The present invention further provides a method for treating individuals having Gaucher disease by administering the novel GIZ or PHCA derivatives as “active-site specific chaperones” for the mutant glucocerebrosidase associated with the disease.

BACKGROUND OF THE INVENTION

Protein Folding

Proteins are synthesized in the cytoplasm, and the newly synthesized proteins are secreted into the lumen of the endoplasmic reticulum (ER) in a largely unfolded state. In general, protein folding is governed by the principle of self assembly. Newly synthesized polypeptides fold into their native conformation based on their amino acid sequences (Anfinsen et al., Adv. Protein Chem. 1975; 29: 205-300). In vivo, protein folding is complicated, because the combination of ambient temperature and high protein concentration stimulates the process of aggregation, in which amino acids normally buried in the hydrophobic core interact with their neighbors non-specifically. To avoid this problem, protein folding is usually facilitated by a special group of proteins called molecular chaperones which prevent nascent polypeptide chains from aggregating, and bind to unfolded protein such that the protein refolds in the native conformation (Hartl, Nature 1996; 381: 571-580).

Molecular chaperones are present in virtually all types of cells and in most cellular compartments. Some are involved in the transport of proteins and permit cells to survive under stresses such as heat shock and glucose starvation. Among the molecular chaperones (Gething et al., Nature 1992; 355: 33-45; Caplan, Trends Cell. Biol. 1999; 9: 262-268; Lin et al., Mol. Biol. Cell. 1993; 4: 109-1119; Bergeron et al., Trends Biochem. Sci. 1994; 19:124-128), Bip (immunoglobulin heavy-chain binding protein, Grp78) is the best characterized chaperone of the ER (Haas, Curr. Top. Microbiol. Immunol. 1991; 167: 71-82). Like other molecular chaperones, Bip interacts with many secretory and membrane proteins within the ER throughout their maturation, although the interaction is normally weak and short-lived when the folding proceeds smoothly. Once the native protein conformation is achieved, the molecular chaperone no longer interacts with the protein. Bip binding to a protein that fails to fold, assemble or be properly glycosylated, becomes stable, and is usually followed by degradation of the protein through the ER-associated degradation. This process serves as a “quality control” system in the ER, ensuring that only those properly folded and assembled proteins are transported out of the ER for further maturation, and improperly folded proteins are retained for subsequent degradation (Hurtley et al., Annu. Rev. Cell. Biol. 1989; 5: 277-307).

Certain missense mutations result in amino acid substitutions that alter the native and proper folding of the protein. To correct these misfoldings, investigations have attempted to use various molecules as artificial chaperones. High concentrations of glycerol, dimethylsulfoxide, trimethylamine N-oxide, or deuterated water have been shown to stabilize the mutant protein and increase the intracellular trafficking of mutant protein in several diseases (Brown et al., Cell Stress Chaperones 1996; 1: 117-125; Burrows et al., Proc. Natl. Acad. Sci. USA. 2000; 97: 1796-801). These compounds are considered non-specific chemical chaperones to improve the general protein folding, although the mechanism of the function is still unknown. The high dosage of this class of compounds required for efficacy makes them difficult or inappropriate to use clinically, although they are useful for the biochemical examination of folding defect of a protein intracellularly. They also lack specificity.

Active Site Specific Chaperones for Enzymes

Co-owned U.S. Pat. Nos. 6,274,597, and 6,774,135 which are incorporated herein by reference, disclose a novel therapeutic strategy for Fabry disease, a lysosomal storage disorder (LSD) caused by a deficiency in lysosomal α-galactosidase A (α-Gal A) activity. α-Gal A deficiency often results from mutations in the gene that encode mutant proteins that result in folding defects. It was discovered that administration of 1-deoxygalactonojirimycin (DGJ), a potent competitive inhibitor of α-Gal A, effectively increased in vitro stability of a mutant α-Gal A (R301Q) at neutral pH. These results were also observed in lymphoblasts established from Fabry patients with the R301Q or Q279E mutations. Surprising, cultivation of the cells with DGJ at sub-inhibitory concentrations resulted in a substantial increase of residual enzyme activity. Furthermore, oral administration of DGJ to transgenic mice overexpressing a mutant (R301Q) α-Gal A substantially elevated the enzyme activity in major organs (Fan et al., Nat. Med. 1999; 5: 112-115).

The principle of this strategy is as the follows. Since the mutant enzyme appears to fold improperly in the ER where pH is neutral, as evidenced by its instability at pH 7.0 in vitro (Ishii et al., Biochem. Biophys. Res. Comm. 1993; 197: 1585-1589), the enzyme would be retarded in the normal transport pathway from the ER to the Golgi apparatus and subjected to rapid degradation. If a mutant enzyme could be efficiently transported to the lysosomes, it may retain normal or near normal kinetic properties and would remain active, because the mutant enzyme is sufficiently stable below pH 5.0. The goal, therefore, was to induce the mutant enzyme to adjust the proper conformation in the ER. In particular, a compound that can induce a stable molecular conformation of the enzyme could serve as an “active-site specific chaperone” (ASSC) or “pharmacological chaperone” to stabilize the mutant enzyme in a proper conformation for transport to the lysosomes. In the case of enzymes, such a compound unexpectedly was discovered to be a competitive inhibitor of the enzyme. Competitive inhibitors of an enzyme are known to occupy the catalytic site of the properly folded enzyme, resulting in stabilization of its correct conformation in vitro. It was found that they also serve as ASSCs or pharmacological chaperones to induce the proper folding of enzyme in vivo, thus rescuing the mutant enzyme from the ER quality control system.

Co-owned U.S. Pat. Nos. 6,583,158, 6,589,964, 6,599,919, and U.S. application Ser. No. 10/304,395 to Fan et al., exemplify the ASSC strategy with numerous other lysosomal storage diseases, including Gaucher disease. These findings demonstrate that this therapeutic strategy of using potent competitive inhibitors as ASSCs to increase the residual enzyme activity in the patient's cells is not limited to Fabry disease, and can be applied to enzyme deficiency diseases of this sort, and particularly to lysosomal storage disorders. In general, effective ASSCs of specific enzymes associated with particular diseases are potent competitive inhibitors of the enzyme. Unexpectedly, a more potent inhibitor of the enzyme acts as a better ASSC for the mutant enzyme (Fan, Trends Pharmacol Sci. 2003; 24: 355-60).

Potent Inhibitors of β-glucocerebrosidase

β-Glucocerebrosidase (GCase, or acid β-glucosidase) is a lysosomal hydrolase that catalyzes the hydrolytic cleavage of glucose from glucosylceramide (Brady et al., Biochem. Biophys. Res. Commun. 1965; 18: 221-225). The deficiency of the enzyme activity results in progressive accumulation of glucosylceramide, a normal intermediate in the catabolism of globoside and gangliosides, in lysosomes of macrophages, leading to Gaucher disease, the most common lysosomal storage disorder (Beutler et al., in The Metabolic and Molecular Bases of Inherited Disease, 8th ed., McGraw-Hill, New York 2001, 3635-3668). Details regarding the disease and therapeutic treatment will be described below.

Sawkar et al have reported that the addition of an inhibitor of GCase to a fibroblast culture medium leads to a 2-fold increase in the activity of N370S GCase, indicating that a potent inhibitor of GCase may be of therapeutic interest in the treatment of Gaucher disease, although the particular inhibitor was not sufficient enough as a therapeutic agent because of high cytotoxocity (Sawkar A. R. et al., Proc Natl Acad Sci USA. 2002; 99(24): 15428-33). Therefore, effort has been taken to design and synthesize potent inhibitors for GCase.

The catalytic mechanism of β-glycosidases is believed to proceed via a covalent glycosyl-enzyme intermediate with a positive charge generated at the anomeric position (Ichikawa et al., J. Am. Chem. Soc. 1998; 120: 3007-3018; Heightman et al., 1999; Angew. Chem. Int. Ed. 1999; 38: 750-770). Ichikawa et al. have designed a class of potent inhibitors for β-glycosidases, 1-N-iminosugars in which a nitrogen atom is at the anomeric position of a monosaccharide (Structure 1A, Isofagomine or hydroxy-piperidine). In a preliminary study, D-glucose-type 1-N-iminosugar (isofagomine, or hydroxypiperidine 1) has been shown to be a potent inhibitor of GCase (U.S. Pat. No. 6,583,158 to Fan et al.). N-alkyl derivatives of 1-deoxynojirimycin (DNJ) are also potent inhibitors of GCase, particularly those have longer alkyl group (greater than C₆ alkyl chain), although DNJ itself and those N-alkyl DNJ with shorter chains are not inhibitory (Structure 1B, N-nonyl 1-deoxynojirimycin) (U.S. Pat. No. 6,583,158). However, these inhibitors are either not specific enough or not potent enough towards to the GCase and not suitable for the treatment of Gaucher disease.

Based on these findings, it was realized that GCase may contain two substrate binding sites in the catalytic domain: one which recognizes the glucosyl residue; the other which recognizes the ceramide moiety (Structure 1C, 6-nonyl hydroxypiperidine, RD-1: recognition domain 1; RD-2: recognition domain 2.). Determination of the crystal structure of GCase revealed an annulus of hydrophobic residues surrounding the entrance to the monosaccharide binding site (Dvir et al., EMBO reports 2003; 4:1-6), suggesting that a hydrophobic moiety attached to a sugar residue with a long alkyl chain is required for the interaction to the hydrophobic amino acid residues.

Among many β-glucosidase inhibitors, isofagomine (IFG) and N-octyl valienamine were found to be the most potent inhibitors of GCase, with IC₅₀ values of approximately 50 nM, or 300 nM, respectively (PCT/JP02/08882 to Ogawa et al; Ogawa et al., Bioorg. Med. Chem. Lett. 1996; 6: 929-932).

In addition, tetrahydroimidazopyridines or glucoimidazole (GIZ) derivatives were also found to be potent inhibitors of β-glucosidases (Panday et al., Helvetica Chimica Acta 2000; 83: 58-75). Although the inhibitors described by Panday were potent, they lack specificity for GCase.

Thus, there remains a need in the art to design or identify specific competitive inhibitors of enzymes, and evaluate them for their ability to act as chaperones for the corresponding mutant enzymes that are associated with numerous LSDs, particularly inhibitors of GCase associated with Gaucher disease, and other disorders resulting from misfolded proteins.

SUMMARY OF THE INVENTION

The present invention provides a compound of the Formula I:

wherein B, R¹, R², R⁵, L¹, and L² are described herein below. The present invention also provides salts, esters and prodrugs of the compounds of Formula I.

The present invention also provides a compound of the Formula II:

wherein B, R¹, R², R⁵, and L are described herein below. The present invention also provides salts, esters and prodrugs of the compounds of Formula II.

Additionally, the present invention described methods of synthesizing compounds according to Formula I.

The present invention also provides salts, esters and prodrugs of the compounds of Formula I and Formula II.

The present invention further provides a method of enhancing in a mammalian cell the activity of GCase by contacting the cell with a compound of Formula I or Formula II in an amount effective to enhance the activity of GCase, i.e., a non-inhibitory amount.

The present invention also provide a method of stabilizing in mammalian cell the GCase by contacting the cell with a compound of Formula I or Formula II in an amount effective to stabilize the GCase.

The present invention also provides compositions comprising a compound of Formula I and Formula II and a pharmaceutically acceptable carrier.

Also provided is a method for treating Gaucher disease by administering to an individual in need of such treatment a pharmaceutical composition comprising a compound of Formula I or Formula II in an amount effective to enhance the activity of GCase.

In addition, the present invention provides a method of inhibiting GCase in a mammalian cell when used at an inhibitory concentrations, by contacting the cell with a compound of Formula I or Formula II.

The present invention provides a method of inhibiting GCase in vitro, when used at an inhibitory concentrations, by contacting the cell with a compound of Formula I or Formula II.

The present invention provides a method of inhibiting β-glucosidases in a mammalian cell when used at an inhibitory concentrations, by contacting the cell with an inhibitory concentration of a compound of Formula I or Formula II.

The present invention provides a method of inhibiting β-glucosidase in vitro, when used at an inhibitory concentrations, by contacting the cell with a compound of Formula I or Formula II.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. Structures of GCase-specific compounds. (a) DNJ, 1-deoxynojirimycin; (b) IFG, isofagomine; (c) GIZ, glucoimidazole; (d) 2-PE-GIZ, 2-phenylethyl glucoimidazole; (e) 2-octyl GIZ, 2-octyl glucoimidazole, and (f) 2-DMB GIZ, 2-dimethylbutyl GIZ.

FIG. 2. Synthesis of glucoimidazole derivatives. (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-iodo-5,6,7,8-tetrahydroimidazo[1,2-α]pyridine (1) was prepared according to the published procedure (Panday et al., Helv. Chim. Acta, 2000, 83: 58-79 and 1997, 80, 979-987). Iodo compound (1) was coupled with phenylacetylene, octyne, or 3,3-dimethyl-1-butyne in the presence of Pd(PPh₃)₄ to afford compound (2), (3), or (4) respectively. Hydrogenation of compound (3), filtration and evaporation of the solvent gave a mixture with a reduced triple bond. Treatment of the mixture with 1 M solution of BCl₃ in CH₂Cl₂ gave compound (6). Compounds (5) and (7) were prepared by the same procedure starting from compound (2) or (4).

FIG. 3. Synthesis of various glucoimidazole derivatives. Various GIZ derivatives can be synthesized according the synthetic scheme shown here, using iodination of protected GIZ, followed by coupling of iodo residues with an alkyne or alkene reagents.

FIG. 4. Inhibitory activity of glucoimidazole derivatives against GCase. The enzyme activity was performed as indicated in the text. ●=glucoimidazole (GIZ); ∘=2-phenylethyl glucoimidazole; and ▴=2-octyl glucoimidazole.

DETAILED DESCRIPTION

The present invention provides the design and synthesis of a novel class of potent competitive inhibitors of GCase, glucimidazole (GIZ), and polyhydroxy-cyclohexyl amine (PHCA) derivatives of glucose, and demonstrates their ability to increase the residual enzyme activity in fibroblasts from Gaucher patients with N370S mutation.

Gaucher Disease

Gaucher disease is a lysosomal storage disorder resulting from the deficient activity of β-glucocerebrosidase (hereinafter referred to as GCase) and the accumulation of its undegraded substrate, glucosylceramide (glucocerebroside), a normal intermediate in the catabolism of globoside and gangliosides (Beutler et al., The Metabolic and Molecular Bases of Inherited Disease, 8th ed. 2001; Scriver, C. R., Beaudet, A. L., Sly, W. S. and Valle, D., ed.) pp. 3635-3668, McGraw-Hill, New York). In some cases, the deficient activity of GCase is caused by mutations in the GCase gene, resulting in misfolding and subsequent degradation of the gene product in the ER. On the basis of the extent, and age of onset of primary neurological involvement, three clinical phenotypes are generally distinguished: (i) the non-neuronopathic variant (type 1, or adult form); (ii) the acute neuronopathic variant (type 2, or infantile form); and (iii) the subacute neuronopathic variant (type 3 or juvenile form). Type 1 Gaucher disease characterized by hepatosplenomegaly, secondary hypersplenism, and skeletal involvement is the most prevalent form and the severity and clinical course of this variant is particularly heterogeneous, ranging from early onset to no clinical manifestations (Grabowski, Gaucher disease: Enzymology, genetics, and treatment. 1993, Plenum Press, New York). In contrast, patients with the neurologic forms (types 2 and 3) are rare. The correlation of clinical severity and genotypes indicates that mild mutations presenting residual enzyme activity often result in type 1 disease, whereas severe or null mutations cause type 3 or type 2 disease.

Gaucher patients have been found from all regions of the world. Particularly, the disease is most common in the Ashkenazi Jewish population, where the frequency of Gaucher disease-causing alleles is approximately 0.0343 (Beutler et al., supra). The incidence is estimated as 1:4,000 (Mathoth et al., Am J Med Genet. 1987; 27: 561-5). Approximately 97% of GCase mutations in Ashkenazi Jews and 75% of the GCase mutations in non-Jewish populations can be detected by screening for the five most common mutations. Of many mutations that have now been documented, the N370S mutation which results in exclusively type 1 Gaucher disease is the most common mutation and is reported to be present in about 6% of the Ashkenazi Jewish population (Beutler et al., Blood 1992; 79: 1662-6). The L444P mutation which causes type 3 disease among homozygotes, exists at polymorphic levels in northern Sweden (Dahl et al., Am J Hum Genet. 1990; 47: 275-8). An insertion of a G at nucleotide position 84 of the cDNA is the second common Jewish mutation. It is found in approximately 0.6% of the Jewish population. This mutation results in a frameshift even before the N-terminus of the mature protein, and an allele bearing this mutation produces no enzyme activity and results in type 2 disease (Beutler et al., Proc Natl Acad Sci USA. 1991; 88: 10544-7).

The gene coding for GCase has been mapped to chromosome 1 at q21 (Ginns et al., Proc Natl Acad Sci USA 1985; 82: 7101-5). The gene for GCase is approximately 7 kb in length and contains 11 exons. GCase cDNA is about 2 kb in length, and active enzyme can be produced from in vivo translation of the cDNA in a variety of eukaryotic cells, including COS cells and insect cells infected with baculovirus (Grabowski et al., Enzyme 1989; 41: 131-42). Human GCase is a homomeric glycoprotein. The mature polypeptide is 497 amino acids with a calculated molecular mass of 55,575. The glycosylated enzyme from placenta has a molecular weight of about 65 kD. Saposin C activates GCase in vitro in the presence of negatively charged phospholipids.

Current Treatment.

Enzyme replacement therapy is currently available to type 1 Gaucher patients. Intravenous infusion of human placental enzyme GCase or recombinant enzymeGCase (modified to expose covered mannose residues) has been shown to be effective at reversing many characteristic clinical manifestations in type 1 Gaucher patients (Kay et al., Trans Assoc. Am. Phys. 1991; 104: 258-264; and Grabowski et al., Pediatr. Res. 1993; 33: 139A). For the type 2 or type 3 patients having neurological involvement, the enzyme replacement therapy (ERT) is less effective, since the enzymes do not cross the blood brain barrier after intravenous infusion.

Another approach to the treatment of Gaucher disease is the use of inhibitors of glucocerebroside synthetase GCase to lower the levels of glucosylceramide and glycolipids (Inokuchi et al., Lipid Res. 1987; 28: 565-71; Platt et al., Biochem. Pharmacol. 1998; 56: 421-430; and Radin et al., Glycoconjugate J. 1996; 13: 153-157). This is known as substrate reduction therapy (SRT). A modest improvement of clinical symptoms in patients was observed after one-year treatment (Cox et al., Lancet 2000; 355: 1481-1485) with small molecule glucose derivatives. SRT, which uses small molecule inhibitors to prevent the synthesis of pathogenic substrates, is under evaluation for several LSDs, and N-butyl 1-deoxynojirimycin (NB-DNJ) has conditional marketing approval in Europe and the U.S. for the treatment of Gaucher disease (Butters et al., Philos Trans R Soc Lond B Biol Sci. 2003; 358: 927-945.). One advantage of this as compared to ERT is that the small molecule inhibitors may potentially cross the blood brain barrier and prevent substrate accumulation in the brain. The most frequent adverse effect was diarrhea, which occurred in 79% of patients shortly after the start of the treatment. It is uncertain whether the long-term reduction of glycolipids will have other adverse effects.

As discussed above, another small molecule approach recently developed is known as active site specific chaperone (ASSC) therapy (Fan et al Nat Med. 1999; 5: 112-115; Fan, Trends Pharmacol Sci. 2003; 24: 355-360). ASSC uses low concentrations of potent enzyme inhibitors, which are specific for the mutant (or wild type) enzyme, to enhance the folding and activity of the mutant proteins in patients with LSDs. Since the active site inhibitors used in ASSC are specific for the disease-causing enzyme, the therapy is targeted to a single protein and a particular metabolic pathway, unlike SRT which inhibits an entire synthetic pathway. Like SRT, the small molecule inhibitors for ASSC have the potential of crossing the blood brain barrier and therefore could be used to treat neurological LSD forms.

Design and Synthesis of Potent Inhibitors for GCase and Effective ASSCs for Gaucher Disease

A more potent inhibitor of an enzyme acts as a better ASSC for the mutant enzyme (Fan, Trends Pharmacol Sci. 2003; 24:355-60). Accordingly, the present invention designed and synthesized a novel class of potent inhibitors for GCase, and used these inhibitors as ASSCs for the enhancement of residual enzyme activity in cells derived from Gaucher patients.

Fan et al. have also determined that ASSC therapy can be used to treat Gaucher disease using hydroxypiperidine (HP) derivatives, which may be administered to individuals having Gaucher disease as “active-site specific chaperones” for the mutant glucocerebrosidase associated with the disease. (U.S. patent application entitled Hydroxy Piperidine Derivatives to Treat Gaucher Disease, filed Nov. 12, 2004).

In addition to enhancing the activity of the mutant (or wild type) enzymes associated with the LSDs, the ASSCs have also been demonstrated to enhance the activity of the corresponding wild-type enzyme (see U.S. Pat. No. 6,589,964 to Fan et al.), thus having utility as co-therapy for enzyme replacement therapy and gene therapy in LSD patients.

The present invention also contemplates the inhibition of β-glucocerebrosidase (GCase). Such inhibition is useful, for example, for studying the effects of a lack of b-glucocerebrosidase in animal models. Since targeted deletion of β-glucocerebrosidase in mammals is lethal, since the knock-out mice cannot be generated for the purposes of evaluating the Gaucher disease state. The present invention contemplates administering an inhibitory amount of the β-glucosidase inhibitors to animals to mimic the Gaucher disease phenotype.

Definitions

As used herein, the following terms have the following definitions.

Chemical

The term ‘alkyl’ refers to a straight or branched C₁-C₂₀ hydrocarbon group consisting solely of carbon and hydrogen atoms, containing no unsaturation, and which is attached to the rest of the molecule by a single bond, e.g., methyl, ethyl, n-propyl, 1-methylethyl (isopropyl), n-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl). The alkyls used herein are preferably C₁-C₈ alkyls.

The term “alkenyl” refers to a C₂-C₂₀ aliphatic hydrocarbon group containing at least one carbon-carbon double bond and which may be a straight or branched chain, e.g., ethenyl, 1-propenyl, 2-propenyl (allyl), iso-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl.

The term “alkynyl” refers to a C₂-C₂₀ straight or branched chain hydrocarbon radicals having at least one carbon-carbon triple bond, e.g. ethynyl, propynyl, butnyl.

The term “cycloalkyl” denotes an saturated, non-aromatic mono- or multicyclic hydrocarbon ring system such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl. Examples of multicyclic cycloalkyl groups include perhydronapththyl, adamantyl and norbornyl groups bridged cyclic group or sprirobicyclic groups, e.g., spiro (4,4) non-2-yl.

The term “cycloalkenyl” an unsaturated, non-aromatic mono- or multicyclic hydrocarbon ring system containing 3 to about 14 carbon atoms, system such as cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl.

The term “cycloalkalkyl” refers to a cycloalkyl as defined above directly attached to an alkyl group as defined above, that results in the creation of a stable structure such as cyclopropylmethyl, cyclobutylethyl, cyclopentylethyl.

The term “aryl” refers to aromatic radicals having in the range of about 6 to about 14 carbon atoms such as phenyl, naphthyl, tetrahydronapthyl, indanyl, biphenyl.

The term “arylalkyl” refers to an aryl group as defined above directly bonded to an alkyl group as defined above, e.g., —CH₂C₆H₅, and —C₂H₄C₆H₅.

The term “heterocyclic ring” or “heterocycyl” refer to a stable 3- to 15-membered ring radical which consists of carbon atoms and from one to five heteroatoms selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur. For purposes of this invention, the heterocyclic ring radical may be a monocyclic, bicyclic or tricyclic ring system, which may include fused, bridged or spiro ring systems, and the nitrogen, phosphorus, carbon, oxygen or sulfur atoms in the heterocyclic ring radical may be optionally oxidized to various oxidation states. In addition, the nitrogen atom may be optionally quaternized; and the ring radical may be partially or fully saturated (i.e., heteroaromatic or heteroaryl aromatic). Examples of such heterocyclic ring radicals include, but are not limited to, azetidinyl, acridinyl, benzodioxolyl, benzodioxanyl, benzofurnyl, carbazolyl, cinnolinyl, dioxolanyl, indolizinyl, naphthyridinyl, perhydroazepinyl, phenazinyl, phenothiazinyl, phenoxazinyl, phthalazinyl, pyridyl, pteridinyl, purinyl, quinazolinyl, quinoxalinyl, quinolinyl, isoquinolinyl, tetrazoyl, imidazolyl, tetrahydroisouinolyl, piperidinyl, piperazinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolidinyl, 2-oxoazepinyl, azepinyl, pyrrolyl, 4-piperidonyl, pyrrolidinyl, pyrazinyl, pyrimidinyl, pyridazinyl, oxazolyl, oxazolinyl, oxasolidinyl, triazolyl, indanyl, isoxazolyl, isoxasolidinyl, morpholinyl, thiazolyl, thiazolinyl, thiazolidinyl, isothiazolyl, quinuclidinyl, isothiazolidinyl, indolyl, isoindolyl, indolinyl, isoindolinyl, octahydroindolyl, octahydroisoindolyl, quinolyl, isoquinolyl, decahydroisoquinolyl, benzimidazolyl, thiadiazolyl, benzopyranyl, benzothiazolyl, benzooxazolyl, furyl, tetrahydrofurtyl, tetrahydropyranyl, thienyl, benzothienyl, thiamorpholinyl, thiamorpholinyl sulfoxide thiamorpholinyl sulfone, dioxaphospholanyl, oxadiazolyl, chromanyl, isochromanyl.

The heterocyclic ring radical may be attached to the main structure at any heteroatom or carbon atom that results in the creation of a stable structure.

The term “heteroarylalkyl” refers to heteroaryl ring radical as defined above directly bonded to alkyl group. The heteroarylalkyl radical may be attached to the main structure at any carbon atom from alkyl group that results in the creation of a stable structure.

The term “heterocyclylalkyl” refers to a heterocylic ring radical as defined above directly bonded to alkyl group. The heterocyclylalkyl radical may be attached to the main structure at carbon atom in the alkyl group that results in the creation of a stable structure.

The substituents in the ‘substituted alkyl’, ‘substituted alkenyl’ ‘substituted alkynyl’ ‘substituted cycloalkyl’ ‘substituted cycloalkalkyl’ ‘substituted cyclocalkenyl’ ‘substituted arylalkyl’ ‘substituted aryl’ ‘substituted heterocyclic ring’, ‘substituted heteroaryl ring,’ ‘substituted heteroarylalkyl’, or ‘substituted heterocyclylalkyl ring’, may be the same or different with one or more selected from the groups hydrogen, hydroxy, halogen, carboxyl, cyano, amino, nitro, oxo (═O), thio (═S), or optionally substituted groups selected from alkyl, alkoxy, alkenyl, alkynyl, aryl, arylalkyl, cycloalkyl, aryl, heteroaryl, heteroarylalkyl, heterocyclic ring, —COOR^(x), —C(O)R^(x), —C(S)R^(x), —C(O)NR^(x)R^(y), —C(O)ONR^(x)R^(y), —NR^(x)CONR^(y)R^(z), —N(R^(x))SOR^(y), —N(R^(x))SO₂R^(y), —(═N—N(R^(x))R^(y)), —NR^(x)C(O)OR^(y), —NR^(x)R^(y), —NR^(x)C(O)R^(y)—, —NR^(x)C(S)R^(y)—NR^(x)C(S)NR^(y)R^(z), —SONR^(x)R^(y)—, —SO₂NR^(x)R^(y)—, —OR^(x), —OR^(x)C(O)NR^(y)R^(z), —OR^(x)C(O)OR^(y)—, —OC(O)R^(x), —OC(O)NR^(x)R^(y), —R^(x)NR^(y)R^(z), —R^(x)R^(y)R^(z), —R^(x)CF₃, —R^(x)NR^(y)C(O)R^(z), —R^(x)OR^(y), —R^(x)C(O)OR^(y), —R^(x)C(O)NR^(y)R^(z), —R^(x)C(O)R^(x), —R^(x)OC(O)R^(y), —SR^(x), —SOR^(x), —SO₂R^(x), —ONO₂, wherein R^(x), R^(y) and R^(z) in each of the above groups can be hydrogen atom, substituted or unsubstituted alkyl, haloalkyl, substituted or unsubstituted arylalkyl, substituted or unsubstituted aryl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkalkyl substituted or unsubstituted heterocyclic ring, substituted or unsubstituted heterocyclylalkyl, substituted or unsubstituted heteroaryl or substituted or unsubstituted heteroarylalkyl.

The term “lipophilic” refers to a functional residue capable of interacting with hydrophobic amino acid residues. Examples of liphophilic groups include but are not limited to C₁-C₁₂ substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted cycloalkyl; substituted or unsubstituted cycloalkenyl; substituted or unsubstituted aryl; substituted or unsubstituted arylalkyl; substituted or unsubstituted heteroaryl; substituted or unsubstituted heterocyclic; substituted or unsubstituted heterocycloalkyl; and substituted or unsubstituted heteroarylalkyl.

The term “halogen” refers to radicals of fluorine, chlorine, bromine and iodine.

The term “hydrogenatable protecting group” refers to protecting groups capable of removal by hydrogenating conditions, for example, benzyl and 4-methoxybenzyl.

The term “acid” refers to Bronsted or Lewis acid such as sulfuric acid, hydrochloride or hydrochloride generated by reaction of acid chloride with alcohol.

The term “organic acid” refers to organic to Bronsted or Lewis acid such as p-toluenesulfonic acid, camphorsulfonic acid.

The term “crown ether” refers to large ring compounds containing several oxygen atoms in a regular pattern such as 12-crown-4,15-crown-5,18-crown-6, dicyclohexano-18-crown-6.

The term “organometallic reagent” refers to a compound that contains a bond between a carbon and a metal atom, such as organolithium, organozinc, organocopper, Grignard reagents.

The term “hydrogenolysis conditions” refers to catalytic hydrogenolysis using catalyst such as, but not limited to, Pd(OH)₂/C, Pd/C, Pt or Raney nickel in the presence of a hydrogen source.

The term “hydrogenation” refers to a chemical reaction in which unsaturated bond between carbon atoms are reduced by attaching a hydrogen atom to each other using catalyst such as, but not limited to, Pd(OH)₂/C, Pd/C, Pt or Raney nickel in the presence of a hydrogen source.

The term “reducing agent” refers to an agent converting a functional group in a molecule from one oxidation state to lower one, such as LiAlH₄, NaBH₄, Zn(BH₄)₂, i-Bu₂AlH and Li-s-Bu₃H.

The term “leaving group” refers to a group that can be substituted by nucleophilic reagent, such as TsO—, TfO—, MsO—, Cl, Br, I.

The term “N-protecting group” refers to groups temporarily protecting amine or imine group to avoid further sites of reaction, such as, but not limited to, 4-methoxybenzyl, benzyl, tert-butyloxycarbonyl, benzyloxycarbonyl.

The term “O-protecting group” refers to groups temporarily protecting an hydroxy to avoid further sites of reaction, such as, but not limited to, 4-methoxybenzyl, benzyl, and trimethylsilyl.

The term “base” refers to organic Lewis base, such as pyridine, triethylamine, diisopropylethylamine.

The term “nucleophilic moiety and nucleophilic reagent” refer to a reagent that forms a bond to its reaction partner (the electrophile) by donating both bonding electrons, such as metal salt of an alcohol, thiol, or 1-alkyne.

The term “a short flexible linker” refers to linkers with linear length of about 6 Å to about 12 Å, preferably about 9 Å.

Biological

As used herein, the term “active site specific chaperone” (ASSC) refers to any molecule including but not limited to a protein, peptide, nucleic acid, carbohydrate, that specifically interacts reversibly with an active site of a protein and enhances formation of a stable molecular conformation. As used herein, “ASSC” does not include endogenous general chaperones present in the ER of cells such as Bip, calnexin or calreticulin, or general, non-specific chemical chaperones such as deuterated water, DMSO, or TMAO.

As used herein, the term “active site” refers to the region of a protein that binds a substrate or binding partner and contributes the amino acid residues that directly participate in the making and breaking of chemical bonds. According to the present invention, the active site encompasses the catalytic domain of the GCase.

The term “wild-type activity” refers to the normal physiological function of a GCase in a cell. Such functionality can be tested by any means known to establish functionality of a protein, specifically, an enzyme. Certain tests may evaluate attributes of a protein that may or may not correspond to its actual in vivo function, but nevertheless are aggregate surrogates of protein functionality, and wild-type behavior in such tests is an acceptable consequence of the protein folding rescue techniques of the invention. One such activity in accordance with the invention is appropriate transport from the endoplasmic reticulum to the particular destination of GCase in the cell, i.e., the lysosome.

The term “functional GCase protein” refers to a GCase protein that has the ability to fold in a proper conformation, achieve its native location in the cell, and have catabolic activity towards glucocerebroside and other lipid substrates. A functional GCase protein includes wild-type GCase proteins (see definitions below), e.g., as depicted in SEQ ID NO: 2.

As used herein, the term “mutant GCase” refers to a GCase translated from a gene containing one or more genetic mutations that result in an altered protein sequence that does not achieve its native conformations under the conditions normally present in the ER. The failure to achieve this conformation results in the GCase being degraded, rather than being transported through its normal pathway in the protein transport system to its proper location within the cell.

Some specific embodiments of such GCase mutations are the N370S mutation and the L444P mutation.

The term “enhancing the activity” of GCase means stabilizing a proper conformation of a mutant GCase protein in the ER so that it folds in a proper conformation, achieves its native location in the cell, and has catabolic activity towards cerebroside, its lipid substrate). This term also refers to increasing the wild-type activity of an exogenously administered GCase protein, i.e., by increasing the stability and extending the in vivo half-life of wild-type GCase, thus, prolonging its activity.

The term “stabilize a proper conformation” refers to the ability of a compound of the invention to induce or stabilize the conformation of a mutated GCase, regardless whether in the ER or other cellular compartments, that is functionally identical to the conformation of the wild type enzyme. By “functionally identical”, the invention means that there may be minor variations in the conformation (indeed almost all proteins exhibit some conformational flexibility in their physiological state) but that conformational flexibility does not result in (1) aggregation, (2) elimination through the endoplasmic reticulum-associated degregation, (3) impairment of enzyme function, and/or (4) improper transport within the cell. This term also refers to the ability of a compound to stabilize a proper conformation of wild-type GCase in viov following exogenously added GCase, or an vitro in a formulation of enzyme.

A “wild-type GCase gene” refers to nucleic acid sequences which encode an ASM protein capable of having functional biological activity in vivo. The wild-type GCase nucleic acid sequence may contain nucleotide changes that differ from the known, published sequence, e.g., SEQ ID NO: 1, as long as the changes result in amino acid substitutions that have little or no effect on the biological activity. As used herein, the term wild-type may also include GCase nucleic acid sequences engineered to encoding a GCase protein capable of increased or enhanced activity relative to the endogenous or native GCase protein.

A “wild-type GCase protein” refers to any protein encoded by a wild-type gene that is capable of having functional biological activity when expressed or introduced in vivo.

Molecular Biology

In accordance with the present invention there may be employed conventional molecular biology, microbiology, and recombinant DNA techniques within the skill of the art. Such techniques are explained fully in the literature. See, e.g., Sambrook, Fritsch & Maniatis, Molecular Cloning: A Laboratory Manual, Second Edition (1989) Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (herein “Sambrook et al., 1989”); DNA Cloning: A Practical Approach, Volumes I and II (D. N. Glover ed. 1985); Oligonucleotide Synthesis (M. J. Gait ed. 1984); Nucleic Acid Hybridization; B. D. Hames & S. J. Higgins eds. (1985); Transcription And Translation (B. D. Hames & S. J. Higgins, eds. 1984); Animal Cell Culture (R. I. Freshney, ed. 1986); Immobilized Cells And Enzymes; IRL Press, (1986); B. Perbal, A Practical Guide To Molecular Cloning (1984); F. M. Ausubel et al. (eds.), Current Protocols in Molecular Biology, John Wiley & Sons, Inc. (1994).

As used herein, the term “isolated” means that the referenced material is removed from the environment in which it is normally found. Thus, an isolated biological material can be free of cellular components, i.e., components of the cells in which the material is found or produced. In the case of nucleic acid molecules, an isolated nucleic acid includes a PCR product, an isolated mRNA, a cDNA, or a restriction fragment. In another embodiment, an isolated nucleic acid is preferably excised from the chromosome in which it may be found, and more preferably is no longer joined to non-regulatory, non-coding regions, or to other genes, located upstream or downstream of the gene contained by the isolated nucleic acid molecule when found in the chromosome. In yet another embodiment, the isolated nucleic acid lacks one or more introns. Isolated nucleic acid molecules include sequences inserted into plasmids, cosmids, artificial chromosomes, and the like. Thus, in a specific embodiment, a recombinant nucleic acid is an isolated nucleic acid. An isolated protein, may be associated with other proteins or nucleic acids, or both, with which it associates in the cell, or with cellular membranes if it is a membrane-associated protein. In a specific embodiment, an isolated GCase protein is a recombinant GCase protein expressed from an expression vector. An isolated material may be, but need not be, purified.

The term “purified” as used herein refers to material that has been isolated under conditions that reduce or eliminate unrelated materials, i.e., contaminants. For example, a purified GCase protein is preferably substantially free of other proteins or nucleic acids with which GCase is normally associated in a cell. As used herein, the term “substantially free” is used operationally, in the context of analytical testing of the material. Preferably, purified ASM substantially free of contaminants is at least 50% pure; more preferably, at least 90% pure, and more preferably still at least 99% pure. Purity can be evaluated by chromatography, gel electrophoresis, immunoassay, composition analysis, biological assay, and other methods known in the art.

The terms “about” and “approximately” shall generally mean an acceptable degree of error for the quantity measured given the nature or precision of the measurements. Typical, exemplary degrees of error are within 20 percent (%), preferably within 10%, and more preferably within 5% of a given value or range of values. Alternatively, and particularly in biological systems, the terms “about” and “approximately” may mean values that are within an order of magnitude, preferably within 10- or 5-fold, and more preferably within 2-fold of a given value. Numerical quantities given herein are approximate unless stated otherwise, meaning that the term “about” or “approximately” can be inferred when not expressly stated.

The term “host cell” means any cell of any organism that is selected, modified, transformed, grown, or used or manipulated in any way, for the production of a substance by the cell, for example the expression by the cell of a mutant or functional mammalian GCase gene, including a DNA or RNA sequence, or the GCase enzyme. Host cells can further be used for preliminary evaluation of the ASSC concept other assays. A “recombinant DNA molecule” is a DNA molecule that has undergone a molecular biological manipulation or engineering.

A “gene” is a sequence of nucleotides which code for a “gene product”. Generally, a gene product is a protein. However, a gene product can also be another type of molecule in a cell, such as an RNA (e.g., a tRNA or a rRNA). For the purposes of the present invention, a gene product also refers to an mRNA sequence which may be found in a cell. As used herein, a gene refers to the nucleotide sequences encoding wild-type or mutant GCase.

The term “express” and “expression” means allowing or causing the information in a GCase gene or DNA sequence to become manifest, for example producing RNA (such as rRNA or mRNA) or a GCase protein by activating the cellular functions involved in transcription and translation of a corresponding GCase gene or DNA sequence, i.e., sequences encoding GCase. A GCase DNA sequence is expressed by a cell to form an “expression product” such as a GCase RNA (e.g., an mRNA or an rRNA) or a GCase protein. The expression product itself, e.g., the resulting GCase RNA or protein, may also said to be “expressed” by the cell.

The term “transfection” means the introduction of a foreign nucleic acid into a cell. The term “transformation” also means the introduction of a “foreign” (i.e., extrinsic or extracellular) gene, DNA or RNA sequence into a host cell so that the host cell will express the introduced gene or sequence to produce a desired substance, in this invention typically an RNA coded by the introduced gene or sequence, but also a protein or an enzyme coded by the introduced gene or sequence. The introduced gene or sequence may also be called a “cloned” or “foreign” gene or sequence, may include regulatory or control sequences (e.g., start, stop, promoter, signal, secretion or other sequences used by a cell's genetic machinery). The gene or sequence may include nonfunctional sequences or sequences with no known function. A host cell that receives and expresses introduced DNA or RNA has been “transformed” and is a “transformant” or a “clone”. The DNA or RNA introduced to a host cell can come from any source, including cells of the same genus or species as the host cell or cells of a different genus or species. As used herein, transfection or transformation will include introduction of sequences encoding functional GCase in individuals having mutated endogenous GCase genes.

The terms “vector”, “cloning vector”, and “expression vector” mean the vehicle by which a GCase DNA or RNA sequence (e.g., a foreign gene) can be introduced into a host cell so as to transform the host and promote expression (e.g., transcription and translation) of the introduced sequence. Vectors include any genetic element, such as a plasmid, phage, transposon, cosmid, chromosome, virus, virion, etc., which is capable of replication when associated with the proper control elements and which can transfer GCase gene sequences between cells. Thus, the term includes cloning and expression vehicles, as well as viral vectors.

The term “expression system” means a host cell and compatible vector under suitable conditions, e.g. for the expression of a GCase protein coded for by foreign DNA carried by the vector and introduced to the host cell. Common expression systems include E. coli host cells and plasmid vectors, insect host cells such as Sf9, Hi5 or S2 cells and Baculovirus vectors and expression systems, and mammalian host cells and vectors.

The term “gene therapy” refers to a method of changing the expression of an endogenous gene by exogenous administration of a gene, i.e., a GCase gene. As used herein, gene therapy also refers to the replacement of a defective GCase gene, or replacement of a missing GCase gene, by introducing a functional gene corresponding to the defective or missing GCase gene into somatic or stem cells of an individual in need. Gene therapy can be accomplished by “ex vivo” methods, in which differentiated or somatic stem cells are removed from the individual's body followed by the introduction of a normal copy of the defective gene into the explanted cells using a viral vector as the gene delivery vehicle. In addition, in vivo direct gene transfer is gene transfer into cells in the individual in situ using a broad range of viral vectors, liposomes, protein DNA complexes, or naked DNA in order to achieve a therapeutic outcome.

The term “recombinant protein” refers to a GCase protein (gene product) encoded by a therapeutic GCase gene carried on a vector. Generally, the cell receiving the vector will lack expression and/or activity of any endogenous GCase protein corresponding to the recombinant protein, or if there is expression of such an endogenous GCase protein, it is of a mutant or at a very low level. In one embodiment, the recombinant protein is produced by a cell in tissue culture for experimental and therapeutic purposes. In another embodiment, the recombinant protein is produced in vivo from cells transformed with vector, wherein the vector or the cells comprising the vector have been administered to a subject, i.e., gene therapy. The recombinant GCase protein will likely be indistinguishable from wild-type protein in normal individuals, i.e., individuals who are not deficient in the protein or do not have Gaucher disease.

Therapeutic and Administration

A “subject” or “patient” is a human or an animal that has developed, or is likely to develop Gaucher disease, more particularly a mammal, preferably a rodent or a primate, and most preferably a human. In one embodiment, the patient is a member of the Ashkenazi Jewish population who has been diagnosed with, or who has been identified as having an increased risk of developing Gaucher disease due inherited mutations in the GCase gene. However, the term “subject” encompasses anyone in the world having, or genetically at risk of developing, Gaucher disease.

The term “prevention” refers to the prevention of the onset of the disease, which means to prophylactically interfere with a pathological mechanism that results in the disease, e.g., Gaucher disease. In the context of the present invention, such a pathological mechanism can be an increase in mutant protein folding and expression of GCase.

The term “treatment” means to therapeutically intervene in the development of a disease in a subject showing a symptom of this disease. In the context of the present invention, these symptoms can include but are not limited to accumulation of GCase in lysosomes, hepatosplenomegaly, psychomotor retardation, pulmonary abnormalities degeneration of bones and joints, and progressive neurodegeneration.

The term “therapeutically effective amount” is used herein to mean an amount or dose of the GIZ or PHCA derivatives of the present invention that is sufficient to increase the level of mutant GCase expression, e.g., to about 3-5%, preferably by about 10%, and more preferably by about 30% of the level found in normal cells, i.e., cells from an individual not having Gaucher disease. Preferably, a therapeutically effective amount can ameliorate or prevent a clinically significant deficit GCase activity in the subject. Alternatively, a therapeutically effective amount is sufficient to cause an improvement in a clinically significant condition in the subject, e.g., amelioration of progressive neurodegeneration in Types 2 and 3 Gaucher patients.

The phrase “pharmaceutically acceptable” refers to molecular entities and compositions that are physiologically tolerable and do not typically produce an allergic or similar untoward reaction, such as gastric upset, and dizziness, when administered to a human. Preferably, as used herein, the term “pharmaceutically acceptable” means approved by a regulatory agency of the Federal or a state government or listed in the U.S. Pharmacopeia or other generally recognized pharmacopeia for use in animals, and more particularly, in humans.

The term “carrier” refers to a diluent, adjuvant, excipient, or vehicle with which the compound is administered. Such pharmaceutical carriers can be sterile liquids, such as water and oils, including those of petroleum, animal, vegetable or synthetic origin, such as peanut oil, soybean oil, mineral oil, sesame oil. Water or aqueous solution saline solutions and aqueous dextrose and glycerol solutions are preferably employed as carriers, particularly for injectable solutions. Suitable pharmaceutical carriers are described in “Remington's Pharmaceutical Sciences” by E. W. Martin.

Novel Compounds and Synthesis Compounds

According to the present invention, the ASSC is a glucoimidazole derivatives as defined in Formula I. In a specific embodiment, the ASSC is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol. The ASSC also can be a C-derivative (and optionally, additionally N-alkylated) of polyhydroxycyclohexyl amine having (i) all hydroxy groups on the cyclohexyl ring in the same configurations as a glucose, providing the amine is attached to the carbon corresponding the anomeric carbon of a glucose; (ii) a short, flexible linker emanating from the corresponding position of the ring oxygen in a pyranose; and (iii) a lipophilic moiety connected to the linker. Since the C-6 position of the glucose residue is not recognized by the most of GCase and β-glucosidases (De Bruyne et al. Eur. J. Biochem. 1979; 102:257-67), the substitutes at the C-6 position can be a hydrogen, hydroxy or hydroxymethyl.

The present invention provides a compound of the Formula I:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen;

-   -   R¹ and R² optionally present are short, flexible linkers linear         length of about 6 Å to about 12 Å, preferably about 9 Å. R¹ and         R² can also be independently C₂-C₆ substituted or unsubstituted:         alkyl, alkenyl, or alkynyl, which are optionally interrupted by         one or more moieties chosen from the group consisting of NH,         NHCOO, NHCONH, NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m)         and —S(O)_(m) NR³;     -   whereas m is 1 or 2, and     -   R³ is independently selected from each occurrence a hydrogen, or         a substituted or unsubstituted: alkyl, alkenyl; alknyl;         cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl;         heterocyclic; heterocyclyalkyl; or heteroarylalkyl, or —C(O)         attached to a C₁-C₆ substituted or unsubstituted alkyl;     -   and pharmaceutically acceptable salts and prodrugs thereof.

In addition, R¹-L¹ or R²-L² can be a hydrogen, if R²-L² or R¹-L¹ is other than a hydrogen, respectively.

R⁵ represents a hydrogen, hydroxy, or hydroxymethyl. In a preferred embodiment, R⁵ is hydroxymethyl.

L¹ and L² are lipophilic groups having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl.

In a preferred embodiment, R¹-L¹ is unsubstituted C₁-C₁₂ alkyl, or more preferably an unsubstituted C₆-C₁₂ alkyl, or more preferably an unsubstituted C₈ alkyl. In another embodiment, R¹-L¹ is an unsubstituted branched C₃₋₁₂ alkyl, or an unsubstituted branched C₆₋₁₂ alkyl, or more preferably an unsubstituted branched C₆ alkyl. In one embodiment, R¹-L¹ is 3,3-dimethylbutyl.

A preferred compound of the invention is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol. Other preferred compounds of the invention include (5R,6R,7S,8S)-5-hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol, (5R,6R,7S,8S)-5-hydroxymethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol, and (5R,6R,7S,8S)-5-hydroxymethyl-2-phenethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.

Collectively, the compounds of Formula I are referred to as “glucoimidazole (GIZ) derivatives.”

The present invention also provides a compound of the Formula II:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen;

-   -   R¹ is a hydrogen, substituted or unsubstituted: alkyl, alkenyl,         alkynyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heteroaryl,         heterocyclic, heterocyclyalkyl, or heteroarylalkyl; —C(O)R³ or         —S(O)_(m)R³;     -   R², optionally present is a short, flexible linker linear length         of about 6 Å to about 12 Å, preferably about 8 Å-10 Å, and more         preferrably about 9 Å. R² can aso be group having 2-6 carbon         atoms comprising a substituted or unsubstituted: alkyl, alkenyl,         or alkynyl, which are optionally interrupted by one or more         moieties chosen from the group consisting of NH, NHCOO, NHCONH,         NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m) and —S(O)_(m)NR³;     -   whereas m is 1 or 2, and R³ is independently selected from each         occurrence a hydrogen, or a substituted or unsubstituted: alkyl,         alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl;         heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl,         or —C(O) attached to a C₁-C₆ substituted or unsubstituted alkyl;         and     -   L is a lipophilic group having 3-12 carbon atoms comprising a         substituted or unsubstituted: alkyl, alkenyl, alkynyl;         cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl;         heterocyclic; heterocycloalkyl; or heteroarylalkyl; and     -   pharmaceutically acceptable salts and prodrugs thereof.

In addition, R²-L can be a hydrogen.

R⁵ represents a hydrogen, hydroxy, or hydroxymethyl. In a preferred embodiment, R⁵ is hydroxymethyl.

Collectively, the compounds of Formula II are referred to as “PHCA derivatives.”

Compounds of the present invention include pharmaceutically acceptable salts and pro-drugs of Formula I and Formula II. Pharmaceutically acceptable salts forming part of this invention include salts derived from inorganics such as L1, Na, K, Ca, Mg, Fe, Cu, Zn, Mn; salts of organic bases such as N,N′-diacetylethylenediamine, glucamine, triethylamine, choline, hydroxide, dicyclohexylamine, metformin, benzylamine, trialkylamine, thiamine; chiral bases like alkylphenylamine, glycinol, phenyl glycinol, salts of natural amino acids such as glycine, alanine, valine, leucine, isoleucine, norleucine, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine, serine; non-natural amino acids such as D-isomers or substituted amino acids; guanidine, substituted guanidine wherein the substituents are selected from nitro, amino, alkyl, alkenyl, alkynyl, ammonium or substituted ammonium salts and aluminum salts. Salts may include acid addition salts where appropriate which are, sulphates, nitrates, phosphates, perchlorates, borates, hydrohalides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, benzoates, salicylates, benzenesulfonates, ascorbates, glycerophosphates, ketoglutarates. Pharmaceutically acceptable solvates may be hydrates or comprise other solvents of crystallization such as alcohols.

Prodrugs are compounds which are converted in vivo to active forms (see, e.g., R. B. Silverman, 1992, “The Organic Chemistry of Drug Design and Drug Action”, Academic Press, Chp. 8). Prodrugs can be used to alter the biodistribution (e.g., to allow compounds which would not typically enter the reactive site of the protease) or the pharmacokinetics for a particular compound. For example, a carboxylic acid group can be esterified, e.g., with a methyl group or an ethyl group, to yield an ester. When the ester is administered to a subject, the ester is cleaved, enzymatically or non-enzymatically, reductively, oxidatively, or hydrolytically, to reveal the anionic group. An anionic group can be esterified with moieties (e.g., acyloxymethyl esters) which are cleaved to reveal an intermediate compound which subsequently decomposes to yield the active compound.

Examples of prodrugs and their uses are well known in the art (See, e.g., Berge et al. (1977) “Pharmaceutical Salts”, J. Pharm. Sci. 66: 1-19). The prodrugs can be prepared in situ during the final isolation and purification of the compounds, or by separately reacting the purified compound with a suitable derivatizing agent. For example hydroxy groups can be converted into esters via treatment with a carboxilic acid in the presence of a catalyst. Examples of cleavable alcohol prodrug moieties include substituted and unsubstituted, branched or unbranched lower alkyl ester moieties, (e.g., ethyl esters), lower alkenyl esters, di-lower alkyl-amino lower-alkyl esters (e.g., dimethylaminoethyl ester), acylamino lower alkyl esters, acyloxy lower alkyl esters (e.g., pivaloyloxymethyl ester), aryl esters (phenyl ester), aryl-lower alkyl esters (e.g., benzyl ester), substituted (e.g., with methyl, halo, or methoxy substituents) aryl and aryl-lower alkyl esters, amides, lower-alkyl amides, di-lower alkyl amides, and hydroxy amides.

Synthesis

Additionally, the present invention describes a method for the synthesis of compounds according to Formula III:

R¹ and R² optionally present are short, flexible linkers having a linear length of about 6 Å to about 12 Å, preferably about 9 Å. R¹ and R² can also be independently C₂-C₆ substituted or unsubstituted: alkyl, alkenyl, or alkynyl, which are optionally interrupted by one or more moieties chosen from the group consisting of NH, NHCOO, NHCONH, NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m) and —S(O)_(m) NR³;

-   -   whereas m is 1 or 2, and R³ is independently selected from each         occurrence a hydrogen, or a substituted or unsubstituted: alkyl,         alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl;         heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl.

In addition, R¹-L¹ or R²-L² can be a hydrogen, if either R²-L² or R¹-L¹ is other than a hydrogen, respectively.

L¹ and L² are lipophilic groups having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl.

Also, pharmaceutically acceptable salts and prodrugs thereof may be synthesized.

This synthesis comprises the steps of:

-   -   a) reacting a compound of the Formula IV:     -    wherein P₁, P₂, P₃ and P₄ are O-protection groups, with         N-iodo-succinimide in a polar aprotic solvent or additional         reactions for selective removal of 3-iodo group from Formula VI         to afford compounds of the Formula V, VI, or VII:     -   b) reacting a compound of the Formula V, VI or VII with a         compound of the Formula VIII or IX:     -    wherein L is a L¹ or L² and R is R¹ or R², in the presence of         Palladium catalyst such as Pd(PPh₃)₄ in a polar aprotic solvent         to afford a compound of the Formula X:     -   c) deprotection of O-protection groups affords Formula III:

Similarly, compounds of corresponding to Formula I and Formula II where R⁵ is hydrogen or hydroxy can be formed by a similar synthesis with modification of the starting material, using standard organic techniques.

Therapeutic Applications

The present invention further provides a method for the prevention or treatment of Gaucher disease, which method comprises increasing the expression or activity of the mutant GCase, or by increasing or stabilizing the activity of recombinant, wild-type replacement GCase (i.e., ERT or gene therapy), in a subject or patient in need of such treatment.

According to the present invention, a “therapeutically effective amount” also means an amount of the GIZ or PHCA derivative that enhances without inhibiting the activity of the GCase protein, i.e., an effective amount enhances more than it inhibits so the net effect is an enhancement. This will generally fall somewhere below the IC₅₀ value of that inhibitor for GCase intracellularly, or below about 50 μM in culture medium.

The small molecule analogue that increases GCase expression or activity is advantageously formulated in a pharmaceutical composition, with a pharmaceutically acceptable carrier. In this context, the GIZ or PHCA derivative is the active ingredient or therapeutic agent.

The concentration or amount of the active ingredient depends on the desired dosage and administration regimen, as discussed below. Suitable dose ranges of the small molecule analogue may include from about 10 μg/kg to about 100 mg/kg of body weight per day.

Combination Therapy GIZ or PHCA Chaperones and Protein Replacement

The pharmaceutical compositions of the invention may also include other biologically active compounds in addition to GIZ or PHCA derivatives of the present invention. For example, in one embodiment, the small molecule may be administered in solution with the replacement, wild-type (or otherwise functional) recombinant GCase during enzyme infusion in replacement therapy. Protein replacement therapy increases the amount of protein by exogenously introducing wild-type or biologically functional protein by way of infusion. This therapy has been developed for many genetic disorders including Gaucher disease. The wild-type enzyme is purified from a recombinant cellular expression system (e.g., mammalian cells or insect cells-see U.S. Pat. No. 5,580,757 to Desnick et al.; U.S. Pat. Nos. 6,395,884 and 6,458,574 to Selden et al.; U.S. Pat. No. 6,461,609 to Calhoun et al.; U.S. Pat. No. 6,210,666 to Miyamura et al.; U.S. Pat. No. 6,083,725 to Selden et al.; U.S. Pat. No. 6,451,600 to Rasmussen et al.; U.S. Pat. No. 5,236,838 to Rasmussen et al.; and U.S. Pat. No. 5,879,680 to Ginns et al.), human placenta, or animal milk (see U.S. Pat. No. 6,188,045 to Reuser et al.).

After the infusion, the exogenous GCase is expected to be taken up by tissues through non-specific or receptor-specific mechanism. In general, the uptake efficiency is not high, and the circulation time of the exogenous protein is short. In addition, the exogenous GCase is unstable and subject to rapid intracellular degradation. Accordingly, it is expected that co-administration with the GIZ or PHCA compounds of the present invention, which act as chaperones for the enzyme, will improve the stability and prevent the degradation of the exogenously administered GCase.

In another embodiment, the small molecule analogue also may be administered in conjunction with, but not necessarily the same composition, as the recombinant wild-type, or otherwise functional, GCase protein. In this embodiment, the replacement GCase protein and the GIZ or PHCA compounds of the present invention are formulated in separate compositions. The GIZ or PHCA derivatives and the replacement GCase may be administered according to the same route, e.g., intravenous infusion, or different routes, e.g., intravenous infusion for the replacement protein, and oral administration for the GIZ or PHCA compound.

GIZ or PHCA Derivatives and Gene Therapy

In addition, the GIZ or PHCA compositions of the present invention may be administered in conjunction with a recombinant vector encoding a wild-type, or otherwise functional GCase gene, i.e., in association with gene therapy. Recently, recombinant gene therapy methods are in clinical or pre-clinical development for the treatment of lysosomal storage disorders, see, e.g., U.S. Pat. No. 5,658,567, for recombinant alpha-galactosidase A therapy for Fabry disease; U.S. Pat. No. 5,580,757, for Cloning and Expression of Biologically Active α-galactosidase A as a Fusion Protein; U.S. Pat. No. 6,066,626, for Compositions and method for treating lysosomal storage disease; U.S. Pat. No. 6,083,725, for Transfected human cells expressing human alpha-galactosidase A protein; U.S. Pat. No. 6,335,011, for Methods for delivering DNA to muscle cells using recombinant adeno-associated virus virions to treat lysosomal storage disease; Bishop, D. F. et al., Proc. Natl. Acad. Sci. USA 1986; 83: 4859-4863; Medin, J. A. et al., Proc. Natl. Acad. Sci. USA 1996; 93: 7917-7922; Novo, F. J., Gene Therapy 1997; 4: 488-492; Ohshima, T. et al., Proc. Natl. Acad. Sci. USA 1997; 94: 2540-2544; Sugimoto Y. et al., Human Gene Therapy 1995; 6: 905-915; Sly et al., Proc. Natl. Acad. Sci. USA 2002; 99(9): 5760-2; Raben et al., Curr. Mol. Med 2002; 2(2): 145-66; Eto et al., Curr. Mol. Med. 2002; 2(1): 83-9; Vogler et al., Pediatr. Dev. Pathol. 2001; 4(5): 421-33; Barranger et al., Expert Opin. Biol. Ther. 2001; 1(5): 857-67; Yew et al., Curr. Opin. Mol. Ther. 2001; 3(4): 399-406; Caillaud et al., Biomed. Pharmacother. 2000; 54(10): 505-12 and Ioannu et al., J. Am. Soc. Nephrol. 2000; 11(8): 1542-7.

It is important to note that in addition to stabilizing the expressed GCase enzyme, the GIZ or PHCA derivative will also stabilize and enhance expression of any endogenous mutant GCase that is deficient as a result of mutations that prevent proper folding and processing in the ER.

Formulations and Administration

According to the invention, the pharmaceutical composition of the invention, e.g., the GIZ or PHCA derivative, can be introduced parenterally, transmucosally, e.g., orally (per os), nasally, or rectally, or transdermally. Parental routes include intravenous, intra-arteriole, intramuscular, intradermal, subcutaneous, intraperitoneal, intraventricular, and intracranial administration.

With respect to combination therapy with protein replacement, in the embodiment where the GIZ or PHCA derivative is administered in the same composition with the replacement GCase enzyme, the formulation is preferably suitable for parenteral administration, including intravenous subcutaneous, and intraperitoneal, however, formulations suitable for other routes of administration such as oral, intranasal, or transdermal are also contemplated.

In one embodiment, transdermal administration is achieved by liposomes. Lipid bilayer vesicles are closed, fluid-filled microscopic spheres which are formed principally from individual molecules having polar (hydrophilic) and non-polar (lipophilic) portions. The hydrophilic portions may comprise phosphate, glycerylphosphato, carboxy, sulfato, amino, hydroxy, choline or other polar groups. Examples of lipophilic groups are saturated or unsaturated hydrocarbons such as alkyl, alkenyl or other lipid groups. Sterols (e.g., cholesterol) and other pharmaceutically acceptable adjuvants (including anti-oxidants such as alpha-tocopherol) may also be included to improve vesicle stability or confer other desirable characteristics.

Liposomes are a subset of these bilayer vesicles and are comprised principally of phospholipid molecules that contain two hydrophobic tails consisting of fatty acid chains. Upon exposure to water, these molecules spontaneously align to form spherical, bilayer membranes with the lipophilic ends of the molecules in each layer associated in the center of the membrane and the opposing polar ends forming the respective inner and outer surface of the bilayer membrane(s). Thus, each side of the membrane presents a hydrophilic surface while the interior of the membrane comprises a lipophilic medium. These membranes may be arranged in a series of concentric, spherical membranes separated by thin strata of water, in a manner not dissimilar to the layers of an onion, around an internal aqueous space. These multilamellar vesicles (MLV) can be converted into Unilamellar Vesicles (UV) with the application of a shearing force.

The pharmaceutical formulations suitable for injectable use include sterile aqueous solutions (where water soluble) or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersion. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and polyethylene glycol), suitable mixtures thereof, and vegetable oils. The proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. The preventions of the action of microorganisms can be brought about by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, and sorbic acid. In many cases, it will be preferable to include isotonic agents, for example, sugars or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, for example, aluminum monosterate and gelatin. The advantage of using liposomes to deliver the ceramide and sphyingomyelin analogues according to the method of the present invention is that liposomes cross the blood-brain barrier. Since Types 2 and 3 Gaucher disease are characterized by neurodegeneration due to an accumulation of glucoceramide, effective targeting to the brain is critical for any therapeutic.

Sterile injectable solutions are prepared by incorporating the purified GCase and GIZ or PHCA derivative in the required amount in the appropriate solvent with various of the other ingredients enumerated above, as required, followed by filter or terminal sterilization. Generally, dispersions are prepared by incorporating the various sterilized active ingredients into a sterile vehicle which contains the basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and the freeze-drying technique which yield a powder of the active ingredient plus any additional desired ingredient from previously sterile-filtered solution thereof.

Preferably the formulation contains an excipient. Pharmaceutically acceptable excipients which may be included in the formulation are buffers such as citrate buffer, phosphate buffer, acetate buffer, and bicarbonate buffer, amino acids, urea, alcohols, ascorbic acid, phospholipids; proteins, such as serum albumin, collagen, and gelatin; salts such as EDTA or EGTA, and sodium chloride; liposomes; polyvinylpyrollidone; sugars, such as dextran, mannitol, sorbitol, and glycerol; propylene glycol and polyethylene glycol (e.g., PEG-4000, PEG-6000); glycerol; glycine or other amino acids; and lipids. Buffer systems for use with the formulations include citrate; acetate; bicarbonate; and phosphate buffers. Phosphate buffer is a preferred embodiment.

The formulation also preferably contains a non-ionic detergent. Preferred non-ionic detergents include Polysorbate 20, Polysorbate 80, Triton X-100, Triton X-114, Nonidet P-40, octyl α-glucoside, octyl β-glucoside, Brij 35, Pluronic, and Tween 20.

For lyophilization of GCase and GIZ or PHCA preparations, the enzyme concentration can be 0.1-10 mg/mL. Bulking agents, such as glycine, mannitol, albumin, and dextran, can be added to the lyophilization mixture. In addition, possible cryoprotectants, such as disaccharides, amino acids, and PEG, can be added to the lyophilization mixture. Any of the buffers, excipients, and detergents listed above, can also be added.

Formulations of GIZ or PHCA compound (with or without the GCase) for inhalation administration may contain lactose or other excipients, or may be aqueous solutions which may contain polyoxyethylene-9-lauryl ether, glycocholate or deoxycocholate. A preferred inhalation aerosol is characterized by having particles of small mass density and large size. Particles with mass densities less than 0.4 gram per cubic centimeter and mean diameters exceeding 5 μm efficiently deliver inhaled therapeutics into the systemic circulation. Such particles are inspired deep into the lungs and escape the lungs' natural clearance mechanisms until the inhaled particles deliver their therapeutic payload (Edwards et al., Science 1997; 276: 1868-1872). Replacement protein preparations of the present invention can be administered in aerosolized form, for example by using methods of preparation and formulations as described in, U.S. Pat. Nos. 5,654,007, 5,780,014, and 5,814,607, each incorporated herein by reference. Formulation for intranasal administration may include oily solutions for administration in the form of nasal drops, or as a gel to be applied intranasally.

Formulations for topical administration to the skin surface may be prepared by dispersing the composition with a dermatological acceptable carrier such as a lotion, cream, ointment, or soap. Particularly useful are carriers capable of forming a film or layer over the skin to localize application and inhibit removal. For topical administration to internal tissue surfaces, the composition may be dispersed in a liquid tissue adhesive or other substance known to enhance adsorption to a tissue surface. Alternatively, tissue-coating solutions, such as pectin-containing formulations may be used.

In preferred embodiments, the formulations of the invention are supplied in either liquid or powdered formulations in devices which conveniently administer a predetermined dose of the preparation; examples of such devices include a needle-less injector for either subcutaneous or intramuscular injection, and a metered aerosol delivery device. In other instances, the preparation may be supplied in a form suitable for sustained release, such as in a patch or dressing to be applied to the skin for transdermal administration, or via erodable devices for transmucosal administration. In instances where the formulation, e.g., the GIZ or PHCA is orally administered in tablet or capsule form, the preparation might be supplied in a bottle with a removable cover or as blister patches.

In the embodiment where the GIZ or PHCA derivative is administered separately than the GCase (or a vector comprising a GCase gene), is administered alone as monotherapy, the compound can be in a form suitable for any route of administration, including but not limited to all of the forms described above. Alternatively, in a preferred embodiment, the small molecule analogue can be formulated for oral administration in the form of tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g., pregelatinized maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g., lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e.g., magnesium stearate, talc or silica); disintegrants (e.g., potato starch or sodium starch glycolate); or wetting agents (e.g., sodium lauryl sulphate). The tablets may be coated by methods well known in the art.

Liquid preparations for oral administration of GIZ or PHCA derivative may take the form of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g., sorbitol syrup, cellulose derivatives or hydrogenated edible fats); emulsifying agents (e.g., lecithin or acacia); non-aqueous vehicles (e.g., almond oil, oily esters, ethyl alcohol or fractionated vegetable oils); and preservatives (e.g., methyl or propyl-p-hydroxybenzoates or sorbic acid). The preparations may also contain buffer salts, flavoring, coloring and sweetening agents as appropriate. Preparations for oral administration may be suitably formulated to give controlled release of the active compound.

The small molecule analogue may also be formulated in rectal compositions such as suppositories or retention enemas, e.g., containing conventional suppository bases such as cocoa butter or other glycerides.

In addition to the formulations described above, the GIZ or PHCA derivative may also be formulated as a depot preparation. Such long acting formulations may be administered by implantation (for example subcutaneously or intramuscularly) or by intramuscular injection. Thus, for example, the GIZ or PHCA derivative may be formulated with suitable polymeric or hydrophobic materials (for example as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt.

Timing. When the replacement GCase protein and GIZ or PHCA derivative are in separate formulations, administration may be simultaneous, or the GIZ or PHCA derivative may be administered prior to, or after the GCase replacement protein. For example, where the replacement protein is administered intravenously, the GIZ or PHCA derivative may be administered during a period from 0 h to 6 h later. Alternatively, the GIZ or PHCA derivative may be administered from 0 to 6 h prior to the protein.

In a preferred embodiment, where the GIZ or PHCA derivative and replacement protein are administered separately, and where the has a short circulating half-life (e.g., small molecule), the GIZ or PHCA derivative may be orally administered continuously, such as daily, in order to maintain a constant level in the circulation. Such constant level will be one that has been determined to be non-toxic to the patient, and optimal regarding interaction with a target replacement protein during the time of administration to confer a non-inhibitory, therapeutic effect.

In another embodiment, the GIZ or PHCA derivative is administered during the time period required for turnover of the replacement GCase protein (which will be extended by administration of the small molecule analogue).

Regardless of the timing, the administration must be such that the concentrations of the GCase and GIZ or PHCA derivative must be such that the small molecule stabilizes, but does not prevent or inhibit the protein's activity in vivo. This also applies where the replacement protein and small molecule are administered in the same formulation.

With respect to the timing of the GIZ or PHCA derivative and gene therapy combination therapy, administration of the small molecule according to the present invention will generally follow delivery of the GCase gene, to allow for expression of the recombinant enzyme by the target cells/tissue. Since the expression of the GCase gene will be sustained for a period of time, for as long as the gene is expressible, the GIZ or PHCA derivative will be remained effective as a chaperone and stabilizer for the recombinant enzyme. Therefore, administration of the chaperone molecule will be necessary for the same period as the gene is expressed.

In a preferred embodiment, since the GIZ or PHCA derivative may have a short circulating half-life, it is preferred that it will be orally administered frequently, such as daily, in order to maintain a constant level in the circulation. Such a constant level will be one that has been determined to be non-toxic to the patient, and optimal regarding interaction with the protein, which will be continuously produced, to confer a non-inhibitory, therapeutic effect.

According to the present invention, since that the therapeutic GCase gene supplements inadequate activity of an endogenous mutant GCase gene, the timing of the small molecule analogue delivery becomes less significant since the effective amount can enhance the activity of the endogenous mutant GCase as well as increase the efficiency of the therapeutic GCase gene product.

The presence of an small molecule chaperone, e.g., the GIZ or PHCA derivatives of the present invention, for the GCase encoded by the administered GCase gene will have the benefit of improving the efficiency of protein processing during synthesis in the ER (i.e., by preventing aggregation), and prolonging in the circulation and tissue the half-life of the GCase, thereby maintaining effective levels over longer time periods. This will result in increased expression in clinically affected tissues. This confers such beneficial effects to the Gaucher patient as enhanced relief, reduction in the frequency of treatment, and/or reduction in the amount of GCase gene administered. This will also reduce the cost of treatment.

Dosages

The amount of the GIZ or PHCA compound effective to stabilize the administered GCase protein and/or endogenous GCase mutant protein can be determined by those skilled in the art. Pharmacokinetics and pharmacodynamics such as half-life (t_(1/2)), peak plasma concentration (C_(max)), time to peak plasma concentration (t_(max)), exposure as measured by area under the curve (AUC), and tissue distribution for both the replacement GCase protein and the small molecule analogue as well as data for the small molecule analogue-replacement GCase protein binding (affinity constants, association and dissociation constants, and valency), can be obtained using ordinary methods known in the art to determine compatible amounts required to stabilize the replacement GCase protein, without inhibiting its activity, and thus confer a therapeutic effect.

Toxicity and therapeutic efficacy of the composition can be determined by standard pharmaceutical procedures, for example in cell culture assays or using experimental animals to determine the LD₅₀ and the ED₅₀. The parameters LD₅₀ and ED₅₀ are well known in the art, and refer to the doses of a compound that is lethal to 50% of a population and therapeutically effective in 50% of a population, respectively. The dose ratio between toxic and therapeutic effects is referred to as the therapeutic index and may be expressed as the ratio: LD₅₀/ED₅₀.

A therapeutically effective dose may be initially estimated from cell culture assays and formulated in animal models to achieve a circulating concentration range that includes the IC₅₀. The IC₅₀ concentration of a compound is the concentration that achieves a half-maximal inhibition of symptoms (e.g., as determined from the cell culture assays). Appropriate dosages for use in a particular individual, for example in human patients, may then be more accurately determined using such information.

Measures of compounds in plasma may be routinely measured in an individual such as a patient by techniques such as high performance liquid chromatography (HPLC) or gas chromatography.

The particular dosage used in any treatment may vary within this range, depending upon factors such as the particular dosage form employed, the route of administration utilized, the conditions of the individual (e.g., patient), and so forth.

According to current methods, the concentration of replacement GCase protein is between 0.05-5.0 mg/kg of body weight, typically administered weekly or biweekly. The protein can be administered at a dosage ranging from 0.1 μg/kg to about 10 mg/kg, preferably from about 0.1 mg/kg to about 2 mg/kg. Regularly repeated doses of the protein are necessary over the life of the patient. Subcutaneous injections maintain longer term systemic exposure to the drug. The GCase is preferably administered intravenously, e.g., in an intravenous bolus injection, in a slow push intravenous injection, or by continuous intravenous injection. Continuous IV infusion (e.g., over 2-6 hours) allows the maintenance of specific levels in the blood.

The optimal concentrations of the GIZ or PHCA derivative will be determined according to the amount required to stabilize the recombinant GCase protein in vivo, in tissue or circulation, without preventing its activity, bioavailability of the small molecule analogue in tissue or in circulation, and metabolism of the small molecule analogue in tissue or in circulation. For example, the concentration of the 2-Octyl GIZ may be determined by calculating the IC₅₀ value of the 2-Octyl GIZ for GCase. Taking into consideration bioavailability and metabolism of the compound, concentrations around the IC50 value or slightly over the IC₅₀ value can then be evaluated based on effects on GCase activity, e.g., the amount of small molecule analogue needed to increase the amount of GCase activity or prolong activity of replacement GCase.

EXAMPLES EXAMPLE 1 Synthesis of GIZ Derivatives

a. (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-(1-octynyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine

(5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-iodo-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine as described by Panday in Helv. Chim. Acta., 83, 58-79 (2000), (300 mg, 0.437 mmol) is combined with [Pd(PPh₃)₄] (0.252 mg, 0.22 mmol), Et₃N (0.27 ml), CuI (8 mg, 0.04 mmol), and 1-octynye (0.19 ml, 1.31 mmol) in DMF (7.5 ml) and is stirred at 80° C. for 7 hours. The reaction mixture is diluted with ether (100 ml) and washed with water and then aq. sat. NaCl. The organic layer is dried over Na₂SO₄ and evaporated using a rotovap. Purification by flash chromatography using CH₂Cl₂ as the eluent gives the title compound as brown syrup. ¹H NMR (300 MHz, CDCl₃): δ7.43-7.14 (m, 21H), 5.15 (d, 1H, J=12 Hz), 4.86-4.75 (m, 4H), 4.62 (d, 1H, J=11.4 Hz), 4.50-4.44 (m, 3H), 4.20-4.16 (m, 1H), 4.10-4.07 (m, 1H), 3.84-3.78 (m, 2H), 3.73-3.70 (m, 1H), 2.39 (t, 2H, J=7.5 Hz), 1.46-1.28 (m, 8H), 0.92-0.88 (m, 3H). MS (ES+): 669 [M+1], 691 [M+Na].

b. (5R,6R,7S,8S)-5-Hydroxymethyl-2-n-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol

A solution of (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-(1-octynyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine (120 mg, 0.179 mmol) in THF/EtOH (2:1) (3 ml) is rapidly stirred with Pd(OH)₂/C (0.1 g) under an atmosphere of hydrogen for 14 h. After filtration of the catalyst, the organic solution is concentrated on a rotovap and the residue is dissolved in CH₂Cl₂ (10 ml). The solution is cooled in an acetone-dry ice bath and a solution of BCl₃ (1.0 M) in CH₂Cl₂ is slowly added. The reaction mixture is warmed room temperature and stirred for 3 hours. The reaction mixture is cooled in an ice-water bath, water added and for 0.5 hour. Most of the solvent is removed using a rotovap and the crude product is purified by chromatography (CHCl₃/MeOH/H₂O 64:25:4). Lyophilization from water gives the title compound as white foam. ¹H NMR (400 MHz, CD₃OD): δ7.22 (s, 1H), 4.56 (d, 1H, J=8 Hz), 4.20-4.16 (m, 1H), 3.98-3.93 (m, 2H), 3.83 (t, 1H, J=8.4 Hz), 3.70 (dd, 1H, J=8.8 Hz and 10 Hz), 2.60 (t, 2H, J=7.2 Hz), 1.67-1.63 (m, 2H), 1.35-1.30 (m, 10H), 0.90 (t, 3H, J=6.8 Hz). MS (ES+): 313 [M+1].

c. (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-(3,3-dimethylbyt-1-ynyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine

In a similar manner to that described in Example 1a, (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-iodo-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine is converted to the title compound. ¹H NMR (300 MHz, CDCl₃): δ7.41-7.14 (m, 20H), 7.13 (s, 1H), 5.10 (d, 1H, J=11.4 Hz), 4.81-4.66 (m, 3H), 4.62 (d, 1H, J=11.4 Hz), 4.49-4.42 (m, 3H), 4.18-4.13 (m, 1H), 4.11-4.06 (m, 2H), 3.84-3.77 (m, 2H), 3.71 (dd, 1H, J=4.8 Hz and 10.5 Hz), 1.31 (s, 9H). MS (ES+): 641 [M+1].

d. (5R,6R,7S,8S)-5-Hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydro-imidazo[1,2-a]pyridine-6,7,8-triol

In a similar manner to that described in Example 1b, (5R,6R,7S,8S)-6,7,8-Tris(benzyloxy)-5-[(benzyloxy)methyl]-2-(3,3-dimethylbyt-1-ynyl)-5,6,7,8-tetrahydro-imidazo[1,2-a]pyridine was converted to the title compound. ¹H NMR (400 MHz, CD₃OD): δ 6.97 (s, 1H), 4.41 (d, 1H, J=8 Hz), 4.09 (dd, 1H, J=2.4 Hz and 12 Hz), 3.86 (dd, 1H, J=4.0 Hz and 12 Hz), 3.79-3.71 (m, 2H), 3.61 (dd, 1H, J=8.4 Hz and 9.2 Hz), 2.48-2.44 (m, 2H), 1.50-1.47 (m, 2H), 0.89 (s, 9H). MS (ES+): 285 [M+1].

EXAMPLE 2 Inhibitory Activities of Glucoimidazole Derivatives Against GCase

Methods. The enzyme activity was assayed with 4-methylumbelliferyl β-glucoside (final concentration 3 mM) as substrate in Reaction Buffer consisting 0.25% sodium taurocholate, 0.1% Triton X-100 in McIlvaine buffer (0.1M citrate and 0.2M phosphate buffer) at pH 5.2. The compounds were added to each reaction mixture individually at the final concentration indicated. After incubation with the diluted human GCase at 37° C. for 30 min, the reaction was stopped by addition of 0.2 M glycine buffer, pH 10.8, the released 4-methylumbelliferone was determined by a fluoremeter at excitation wavelength of 355 nm and emission wavelength at 460 nm, respectively. The relative enzyme activity was calculated as a percentage to those of reactions without inhibitors. IC₅₀ was calculated using Prism sigmoid plot.

Results. GIZ and 2-PE-GIZ were reported to be potent inhibitors for β-glucosidases (Panday et al., Helvetica Chimica Acta 2000; 83: 58-75). The proposed inhibitory mechanism of these compounds concerns the “shape” or conformation of these molecules and its similar to the transition state of the substrate (Heightman et al., Angew. Chem. Int. Ed. 1999; 38:750-770). 2-Octyl GIZ and 2-DMB-GIZ ((5R,6R,7S,8S)-5-Hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol) was synthesized (see synthetic scheme in FIG. 1) and the inhibitory activities against human GCase were shown in FIG. 4 and Table 1. The IC50 values of GIZ and 2-PE-GIZ against GCase were 87 nM and 1.1 nM, respectively, indicating that they are potent inhibitors of GCase. It was found that replacing the phenylethyl group with octyl or dimethlbutyl groups at the same position in 2-PE-GIZ increased the inhibitory potency approximately 15-fold or 37-fold, supporting the present findings that a lipophilic moiety with a short, flexible chain significantly contributes the inhibitory activity toward GCase. TABLE 1 Inhibitory activity against GCase. Inhibitors Entry IC₅₀ (nM) Glucoiminozole (GIZ) 87 2-Octyl GIZ 6 0.07 2-Phenylethyl GIZ 5 1.1 2-Dimethylbutyl GIZ 7 0.03

EXAMPLE 3 Chaperone Activity of GIZ for GCase in Gaucher Cells

Methods. Fibroblasts established from Gaucher patients with N370S/N370S mutation were cultured in DMEM medium supplemented with 10% fetal bovine serum and antibiotics at 37° C. under 5% CO₂. The GIZ was added into the culture medium at the final concentrations for 4 days prior to the assay. After washing the cells with phosphate-buffered saline, the cells were harvested and homogenized in the presence of 0.25% (w/v) sodium taurocholate and 0.1% (v/v) Triton X-100 in McIlvaine buffer (pH 5.2, Reaction Buffer), and 10 μl of the lysate was used for the determination of residual enzyme activity. The activity of the GCase was determined with 3 mM 4-MU-β-Glc in the Reaction Buffer at 37° C. for 1 hr as conduritol B epoxide (CBE)-sensitive activity in parallel assays without or with pre-incubation with CBE at 1.25 mM for 30 min at room temperature. Protein concentrations in the cell lysates were determined using micro BCA protein assay kit from Pierce.

Results. In order to examine the ability of the novel compounds to rescue mutant enzyme activity from degradation in the ER, GIZ was added at various concentrations in the culture medium of fibroblasts established from Gaucher patient with homozygous N370S mutation. The residual enzyme activity in patient cells cultivated with inhibitors were shown to be increased approximately 2-fold. The optimal concentration for the maximum enhancement was approximately at 300 μM. Incubation of the cells with GIZ at higher concentrations results in the reduction of the residual enzyme activity, presumably caused by inhibition of GIZ at those concentrations. It has been indicated that optimal concentration for chaperone activity is dependent on the potency of inhibitory activity and the bioavailability (Fan et al., Trends Pharmacol Sci. 2003; 24: 355-60). The combination of the highest inhibitory activity and good permeability may contribute the lower optimal concentration as a chaperone for the GCase activity in Gaucher disease. 

1. A compound of the Formula I:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen; R¹ and R² are optionally present, are flexible linkers with a linear length of about 6 Å to about 12 Å; L¹ and L² are lipophilic groups having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl; and R⁵ is a hydrogen, hydroxy, or hydroxymethyl.
 2. A compound of the Formula I:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen; R¹ and R² are independently C₂-C₆ substituted or unsubstituted: alkyl, alkenyl, or alkynyl, which are optionally interrupted by one or more moieties chosen from the group consisting of NH, NHCOO, NHCONH, NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m) and —S(O)_(m) NR³; L¹ and L² are lipophilic groups having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl; wherein R¹-L¹ or R²-L² can be a hydrogen, if either R²-L² or R¹-L¹ is other than a hydrogen; R³ is independently selected from each occurrence a hydrogen, or a substituted or unsubstituted: alkyl, alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl, or —C(O) attached to a C₁-C₆ substituted or unsubstituted alkyl; m is 1 or 2; and R⁵ is a hydrogen, hydroxy, or hydroxymethyl; and pharmaceutically acceptable salts and prodrugs thereof.
 3. A method for synthesizing a compound of the Formula III:

wherein R¹ and R² are independently C₂-C₆ substituted or unsubstituted: alkyl, alkenyl, or alkynyl, which are optionally interrupted by one or more moieties chosen from the group consisting of NH, NHCOO, NHCONH, NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m) and —S(O)_(m) NR³; L¹ and L² are lipophilic groups having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl; wherein R¹-L¹ or R²-L² can be a hydrogen, if either R²-L² or R¹-L¹ is other than a hydrogen; R³ is independently selected from each occurrence a hydrogen, or a substituted or unsubstituted: alkyl, alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl, or —C(O) attached to a C₁-C₆ substituted or unsubstituted alkyl; m is 1 or 2; and pharmaceutically acceptable salts and prodrugs thereof; and comprising the steps of: a) reacting a compound of the Formula IV:

 wherein P₁, P₂, P₃ and P₄ are O-protection groups, with N-iodo-succinimide in a polar aprotic solvent or additional reactions for selective removal of 3-iodo group from Formula VI to yield compounds of the Formula V, VI, or VII:

b) reacting a compound of the Formula V, VI or VII with a compound of the Formula VIII or IX:

 wherein L is a L¹ or L² and R is R¹ or R²,  in the presence of palladium catalyst in a polar aprotic solvent to yield a compound of the Formula X:

 deprotecting the O-protection groups to yield formula III:


4. The compound according to claim 2 wherein R²-L² is hydrogen.
 5. The compound according to claim 2 wherein B is hydroxy.
 6. The compound according to claim 2 wherein R⁵ is hydroxy.
 7. The compound according to claim 2 wherein R⁵ is hydroxymethyl.
 8. The compound according to claim 4 wherein R¹-L¹ is unsubstituted C₁-C₁₂ alkyl.
 9. The compound according to claim 8 wherein R¹-L¹ is unsubstituted C₆-C₁₂ alkyl.
 10. The compound according to claim 9 wherein R¹-L¹ is unsubstituted C₈ alkyl.
 11. The compound according to claim 8 wherein and R¹-L¹ is unsubstituted branched C₃₋₁₂ alkyl.
 12. The compound according to claim 11 wherein R¹-L¹ is unsubstituted branched C₆₋₁₂ alkyl.
 13. The compound according to claim 12 wherein R¹-L¹ is unsubstituted branched C₆ alkyl.
 14. The compound according to claim 4 wherein R¹-L¹ is 3,3-dimethylbutyl.
 15. A compound according to claim 2 comprising (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 16. A compound according to claim 2 comprising (5R,6R,7S,8S)-5-hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 17. A compound of the Formula II:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen; R¹ is a hydrogen, substituted or unsubstituted: alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heteroaryl, heterocyclic, heterocyclyalkyl, or heteroarylalkyl; —C(O)R³ or —S(O)_(m)R³; R² optionally present, is a flexible linker with a linear length of about 6 Å to about 12 Å; L is a lipophilic group having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl; R³ is independently selected from each occurrence a hydrogen, or a substituted or unsubstituted: alkyl, alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl, or —C(O) attached to a C₁-C₆ substituted or unsubstituted alkyl; m is 1 or 2; and R⁵ is a hydrogen, hydroxy, or hydroxymethyl, and pharmaceutically acceptable salts and prodrugs thereof.
 18. A compound of the Formula II:

wherein B is hydrogen, hydroxy, N-acetamino, or halogen; R¹ is a hydrogen, substituted or unsubstituted: alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, arylalkyl, heteroaryl, heterocyclic, heterocyclyalkyl, or heteroarylalkyl; —C(O)R³ or —S(O)_(m)R³; R^(2,) optionally present, is a C₂-C₆ substituted or unsubstituted: alkyl, alkenyl, or alkynyl, which is optionally interrupted by one or more moieties chosen from the group consisting of NH, NHCOO, NHCONH, NHCSO, NHCSNH, CONH, NHCO, NR³, O, S, S(O)_(m) and —S(O)_(m) NR³; L is a lipophilic group having 3-12 carbon atoms comprising a substituted or unsubstituted: alkyl, alkenyl, alkynyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocycloalkyl; or heteroarylalkyl; R³ is independently selected from each occurrence a hydrogen, or a substituted or unsubstituted: alkyl, alkenyl; alknyl; cycloalkyl, cycloalkenyl; aryl; arylalkyl; heteroaryl; heterocyclic; heterocyclyalkyl; or heteroarylalkyl, or —C(O) attached to a C₁-C₆ substituted or unsubstituted alkyl; m is 1 or 2; and R⁵ is a hydrogen, hydroxy, or hydroxymethyl; and pharmaceutically acceptable salts and prodrugs thereof.
 19. The compound according to claim 18 wherein R⁵ is hydroxy.
 20. A method of inhibiting glucocerebrosidase, comprising contacting a glucocerebrosidase with a compound as set forth in claim 1, in an amount effective to inhibit the glucocerebrosidase.
 21. The method of claim 20, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 22. The method of claim 20, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 23. The method of 20, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 24. The method of claim 20, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-phenethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 25. A method of inhibiting glucocerebrosidase comprising contacting glucocerebrosidase with a compound as set forth in claim 18, in an amount effective to inhibit the glucocerebrosidase.
 26. A method of inhibiting glucocerebrosidase in a mammalian cell comprising contacting the cell with an inhibitory amount of a compound as set forth in claim
 1. 27. The method of claim 26, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 28. The method of claim 26, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 29. The method of claim 26, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 30. The method of claim 26, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-phenethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 31. A method of inhibiting glucocerebrosidase in a mammalian cell comprising contacting the cell with an inhibitory amount of a compound as set forth in claim
 18. 32. A method of enhancing in a mammalian cell the activity of glucocerebrosidase, comprising contacting the cell with a compound as set forth in claim 1 in an amount effective to enhance the activity of glucocerebrosidase, and wherein the effective amount does not inhibit glucocerebrosidase activity.
 33. The method of claim 32, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 34. A method of enhancing in a mammalian cell the activity of glucocerebrosidase, comprising contacting the cell with a compound as set forth in claim 18 in an amount effective to enhance the activity of glucocerebrosidase, and wherein the effective amount does not inhibit glucocerebrosidase activity.
 35. A method of stabilizing glucocerebrosidase, comprising contacting the glucocerebrosidase with a compound as set forth in claim 1, wherein the compound binds reversibly to the glucocerebrosidase, in an amount effective to stabilize the glucocerebrosidase.
 36. The method of claim 35, wherein the compound is (5R,6R,7S,8S)-5-Hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 37. The method of claim 35, wherein the compound is (5R,6R,7S,8S)-5-Hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 38. The method of claim 35, wherein the compound is (5R,6R,7S,8S)-5-Hydroxymethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 39. The method of claim 35, wherein the compound is (5R,6R,7S,8S)-5-Hydroxymethyl-2-phenethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 40. A method of stabilizing glucocerebrosidase, comprising contacting the glucocerebrosidase with a compound as set forth in claim 18, wherein the compound binds reversibly to the glucocerebrosidase, in an amount effective to stabilize the glucocerebrosidase.
 41. A pharmaceutical composition comprising a compound as set forth in claim 1 and a pharmaceutically acceptable carrier.
 42. The method of claim 41, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-octyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 43. The method of claim 41, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-(3,3-dimethylbutyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 44. The method of claim 41, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 45. The method of claim 41, wherein the compound is (5R,6R,7S,8S)-5-hydroxymethyl-2-phenethyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-6,7,8-triol.
 46. A pharmaceutical composition comprising a compound as set forth claim 18 and a pharmaceutically acceptable carrier.
 47. A method of inhibiting a β-glucosidase, comprising contacting the β-glucosidase with a compound as set forth in claim 1, wherein the compound binds reversibly to the 13-glucosidase, in an amount effective to inhibit the β-glucosidase.
 48. A method of inhibiting a β-glucosidase, comprising contacting the β-glucosidase with a compound as set forth in claim 18, wherein the compound binds reversibly to the β-glucosidase, in an amount effective to inhibit the β-glucosidase.
 49. A method for treating Gaucher disease comprising administering to an individual in need of such treatment a pharmaceutical composition as set forth in claim 1 in an amount effective to enhance the activity of glucocerebrosidase.
 50. The method of claim 49, wherein the treatment further comprises administering to the individual a functional glucocerebrosidase enzyme.
 51. The method of claim 49, wherein the treatment further comprises administering to the individual a vector functional glucocerebrosidase gene.
 52. A method for treating Gaucher disease comprising administering to an individual in need of such treatment a pharmaceutical composition as set forth in claim 18 in an amount effective to enhance the activity of glucocerebrosidase.
 53. The method of claim 52, wherein the treatment further comprises administering to the individual a functional glucocerebrosidase enzyme.
 54. The method of claim 52, wherein the treatment further comprises administering to the individual a vector functional glucocerebrosidase gene.
 55. A glucoimidazole derivative having a short flexible linker emanating from the corresponding ring oxygen position in a pyranose and a lipophilic moiety connected to the linker; and pharmaceutically acceptable salts of such derivatives.
 56. A polyhydroxycyclohexyl amine derivatives having a short flexible linker emanating from the corresponding ring oxygen position in a pyranose and a lipophilic moiety connected to the linker; and pharmaceutically acceptable salts of such derivatives. 